Number Properties Chapter Seven pg. 90 Gen. Question 4th Ed.

[afvatcha]

In the number properties guide, the book gives an example (pg. 90) of how to simplify fractions. When getting rid of the deonominators, in this instance the book suggests, that you should multiply by 2/2 and 3/3. Why? I always thought that if there is, let's say, a three in the denominator, multiply by three or in other words 3/1. Could someone please tell me where I am going wrong?

Thanks!

[tim]

when changing fractions to a common denominator, you need to make sure you don't actually change the fraction. multiplying by 3/1 changes the actual number; on the other hand, multiplying by 3/3 is multiplying by 1, which leaves the number the same while giving you the denominator you want..